title: Effect of cortisol levels on working memory performance in elderly subjects with Alzheimer's disease.
abstract: BACKGROUND
  Subjects with Alzheimer's disease (AD) have elevated cortisol levels as a result of hypothalamic-pituitary-adrenal (HPA) axis dysfunction. Acute administration of hydrocortisone has been associated with working memory (WM) performance in young adults.
  
  
  OBJECTIVE
  To investigate whether cortisol levels are associated with WM performance in subjects with AD.
  
  
  METHODS
  Eighty subjects were included, comprising 40 patients with mild AD and 40 healthy elderly controls. WM was assessed using the Digit Span Backward test (DSB). Saliva samples were collected to determine cortisol levels.
  
  
  RESULTS
  AD subjects had poorer performance on the DSB than controls (p=0.002) and also presented higher levels of cortisol than control group (p=0.04). No significant correlation was observed between the DSB and cortisol levels in both groups (r= -0.29).
  
  
  CONCLUSIONS
  In this study, elevated cortisol levels were not associated with poorer WM performance in patients with AD or in healthy elderly subjects.
authors.affiliation: Department of Medical-Surgical Nursing, School of Nursing, University of São Paulo, São Paulo, SP, Brazil.
authors.forename: Juliana Nery de
authors.initials: JN
authors.lastname: Souza-Talarico
authors.forename: Paulo
authors.initials: P
authors.lastname: Caramelli
authors.forename: Ricardo
authors.initials: R
authors.lastname: Nitrini
authors.forename: Eliane Corrêa
authors.initials: EC
authors.lastname: Chaves
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000378:metabolism* / Q000503:physiopathology; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000032:analysis*; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology*; D009483:Neuropsychological Tests; D012463:Saliva / Q000737:chemistry*
chemical_list: D006854:Hydrocortisone